We did indeed install the call sign database for the first time on the new computer, but the "no-shows" still didn't show. I am not aware that we made any filter settings that would exclude all call signs after installing the database. My friend is an LoTW user and has the visual flags set to show LoTW users among the decoded signals (mark in upper left corner), but there is no filter set that would exclude any or all call signs. In any case I would believe that no matter which filter setting was in use, there would be some signals over one hour or more that would meet the filter criteria and appear in the decoded fields. Only when we changed to two lines of decoded call signs, the decoded call signs appeared.
I still have no idea what happened, but you can store it at the back of the head if something similar should show up from others.
No matter what, many thanks for the work you do to improve the user friendliness of the weak signal mode softwares.
73 Frode LA6VQ